Melissa Joan Hart, star of “Sabrina, the Teenage Witch,” was horrified when photos of her post-baby body surfaced in the media last year. But she got sweet revenge when she unveiled her 113-pound bikini body to the world. Find out how she lost weight in this Lifescript exclusive…

It has been a year of successes for the 33-year-old Hart, best known for her role on the ABC sitcom, “Sabrina, the Teenage Witch.”

First, she lost 42 pounds following the birth of her second son. Then she opened a candy store with her mother. The icing on the cake? She’s joining season 9 of "Dancing With the Stars."

“I’m beside myself with excitement, nerves and anticipation” for DWTS, Hart said. “The costumes, the lessons and all that goes with it should be a blast.”

No question, Hart is on the move, on and off stage. She and rocker hubby Mark Wilkerson are shuttling between Los Angeles and Connecticut as her mother recovers from a June surgery for a brain tumor.

Hart grew up in front of cameras, beginning her acting career when she was just 4 years old. But a life detailed in the media didn’t prepare her for the unflattering photos that surfaced last year. They were taken only three months after her second son, Braydon, now 18 months, was born. (Her eldest, Mason, is 3.)

But now she has her bikini body back — and showed it off in People magazine. How’d she do it?

In this Lifescript exclusive, Hart talks about weight loss, motherhood, her new business venture and how she keeps the romance going with her husband.

You looked great on your June People magazine cover. Was it difficult to get back into shape after the second baby?It was hard, but I had the most amazing motivation: Wearing a bikini in front of millions of people will really make you stick to your diet.

Even though I haven't had a lot of weight on me for the last few months, pictures show me a bit bigger.

It was important for me — personally and professionally — to lose the weight and let people know.

Which came first? The offer for the bikini cover or the weight loss?A bit of both. I had already started losing weight and People wanted to do a "Body After Baby" piece. When they wanted to do a cover, I kicked my fitness routine into high gear.

Did you hire a trainer?I’ve worked out with Mark Havari for years. Now I go to his gym, Pulse Fitness in Sherman Oaks, Calif., and train with him twice a week. Previously, I went to his classes a couple of nights a week.

I also have a nutritionist, Derek Johnson from New Metabolism in Brentwood, Calif., and just started to apply all the lessons they taught me over the years.

What diet did you follow?I did a cleanse [at the start of the diet]. Last year, I cut out sugar. Then, when I was done with breast-feeding, I cut out dairy. When I stepped it up, I cut out starches.

I also started drinking more water and made sure I got enough rest.

I tightened my diet in little ways, like swapping ketchup for salsa.

How did you prevent stretch marks during your pregnancy? I have really good genes. My mom and I don’t have stretch marks, but we have “elephant skin” on our stomachs: a little wrinkly, loose skin.

I just have really light stretch marks on my hips that you can see only in bright sunlight.

I would use all those lotions and potions to avoid stretch marks. But my mom doesn't have any and she had seven kids – so part of avoiding them has to be hereditary.

You began your career so young, so you’re used to media scrutiny. But how did you handle the mean comments about your weight?I had to think of what was most important to me and, at the time, that was breast-feeding my baby. I didn't worry about what anybody was saying because I was concerned with having a healthy child.

Because when you are breast-feeding, you need to eat more calories.You definitely need calcium too. Your body will give everything to the baby ... when you're breast-feeding.

The old wives' tale that says you lose a tooth with every baby actually refers to calcium loss. My mom made a big point of my calcium intake, so I would never cut back on dairy while breast-feeding.

Are you more sympathetic to other stars’ negative press?Anybody can look bad when a picture is taken from a bad angle.

Some people might look great in person and look terrible in pictures. Or look great in pictures and terrible in person. You just never know.

Everybody has something about themselves they don't like.Even supermodels. Even they get cellulite. It just happens.

How do you balance your work and personal life?It’s tough. Right now, I’m able to do this [interview] because one of my sons is sleeping and the other one is at the zoo.

That’s the challenge. We have a calendar at home where we enter our daily duties so my husband, our nanny and I can stay on the same page. Each day is different.

I found it hard to fit exercise into the daily schedule. I realized I have to go to the gym first thing in the morning – otherwise I don’t go.

How do you and Mark keep the romance going? We try to do date nights on weeknights because Fridays and Saturdays are so crazy — restaurants and movie theaters are packed.

We actually don't like to go on date nights too often, because if the kids are asleep, we feel like we’re wasting our chance for rest.

A lot of times, we have day dates. We sit at Starbucks or have a lunch. We get a little time for some peace and quiet. At night, we get into bed and watch "House" or "Grey's Anatomy."

You’ve done drama, but you’re known for your comedy. Do you ever wish for a role where you could showcase your dramatic chops?Oh, yes, most people are terrified of doing comedy, but I’m more terrified of drama. It’s not where I feel at home, so I have to work harder at it.

But I’ll take any challenge that comes my way.

I’m an actor. I like to play. I like to be different people with different personalities, and it’s great to play a role that terrifies me. The more I do that, the more comfortable I’ll get with it.

Even though you’re now juggling family life with acting in TV movies, are you ready to go back to a TV series?I would love to. That’s the best work in Hollywood – it’s the most 9 to 5.

That’s true if it’s a comedy series, but if it’s a drama, the days are long.I would definitely want to do a comedy, but I wouldn't shy away from being a new cast member on, say, "Grey's Anatomy."

The thing is, it’s all temporary. It’s not as if it's going to go on until I am 60. TV shows usually don't last more than five years.

You just take what comes. If it’s fun and exciting, you do it and make it work.

You also did some directing. Does that still appeal to you?I love directing because it’s the most creative part of the process. You get complete control from beginning to end. You can make that project anything you want.

But because it’s more time-consuming, I don't do it too often. It’s hard work, but it’s really fun and exciting. It’s the most rewarding to me of all the things in the industry.

Everywhere my mom and I travel, we wonder, "Where are the good places?"

In Italy, we found a cute gelato place and said, " Look what they did here."

We collected ideas without knowing it.

From there we decided, "Let's do a cute store called SweetHarts."

Two years ago, we started looking for real estate and then realized we didn't know what we were doing. So we got some partners. I designed it and worked with people who knew more about the industry.

How much of a temptation is it?The only thing I eat there is the non-fat frozen yogurt.

Paulette Cohn is a writer for Entertainment Tonight and covers celebrity health for Lifescript.

Do You Have A Sweet Tooth?Whether you spread gooey globs of strawberry jam on your toast each morning or go all out with a hot fudge sundae every night for dessert, indulging in sugar is a special treat. Do you know the difference between an occasional sugar craving and a sweet tooth? Find out with our quiz.